pythongh-121272: move __future__ import validation from compiler to s…

…ymtable (python#121273)
Akasurde · Jul 3, 2024 · f767f75 · f767f75
1 parent 3908aed
commit f767f75
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Showing 2 changed files with 24 additions and 16 deletions.
diff --git a/Python/compile.c b/Python/compile.c
@@ -77,14 +77,6 @@ typedef struct _PyCfgBuilder cfg_builder;
 #define LOCATION(LNO, END_LNO, COL, END_COL) \
  ((const _Py_SourceLocation){(LNO), (END_LNO), (COL), (END_COL)})
 
-/* Return true if loc1 starts after loc2 ends. */
-static inline bool
-location_is_after(location loc1, location loc2) {
- return (loc1.lineno > loc2.end_lineno) ||
- ((loc1.lineno == loc2.end_lineno) &&
- (loc1.col_offset > loc2.end_col_offset));
-}
-
 #define LOC(x) SRC_LOCATION_FROM_AST(x)
 
 typedef _PyJumpTargetLabel jump_target_label;
@@ -3847,14 +3839,6 @@ compiler_from_import(struct compiler *c, stmt_ty s)
  PyTuple_SET_ITEM(names, i, Py_NewRef(alias->name));
  }
 
- if (location_is_after(LOC(s), c->c_future.ff_location) &&
- s->v.ImportFrom.module && s->v.ImportFrom.level == 0 &&
- _PyUnicode_EqualToASCIIString(s->v.ImportFrom.module, "__future__"))
- {
- Py_DECREF(names);
- return compiler_error(c, LOC(s), "from __future__ imports must occur "
- "at the beginning of the file");
- }
  ADDOP_LOAD_CONST_NEW(c, LOC(s), names);
 
  if (s->v.ImportFrom.module) {

diff --git a/Python/symtable.c b/Python/symtable.c
@@ -1660,6 +1660,27 @@ has_kwonlydefaults(asdl_arg_seq *kwonlyargs, asdl_expr_seq *kw_defaults)
  return 0;
 }
 
+static int
+check_import_from(struct symtable *st, stmt_ty s)
+{
+ assert(s->kind == ImportFrom_kind);
+ _Py_SourceLocation fut = st->st_future->ff_location;
+ if (s->v.ImportFrom.module && s->v.ImportFrom.level == 0 &&
+ _PyUnicode_EqualToASCIIString(s->v.ImportFrom.module, "__future__") &&
+ ((s->lineno > fut.lineno) ||
+ ((s->lineno == fut.end_lineno) && (s->col_offset > fut.end_col_offset))))
+ {
+ PyErr_SetString(PyExc_SyntaxError,
+ "from __future__ imports must occur "
+ "at the beginning of the file");
+ PyErr_RangedSyntaxLocationObject(st->st_filename,
+ s->lineno, s->col_offset + 1,
+ s->end_lineno, s->end_col_offset + 1);
+ return 0;
+ }
+ return 1;
+}
+
 static int
 symtable_visit_stmt(struct symtable *st, stmt_ty s)
 {
@@ -1914,6 +1935,9 @@ symtable_visit_stmt(struct symtable *st, stmt_ty s)
  break;
  case ImportFrom_kind:
  VISIT_SEQ(st, alias, s->v.ImportFrom.names);
+ if (!check_import_from(st, s)) {
+ VISIT_QUIT(st, 0);
+ }
  break;
  case Global_kind: {
  Py_ssize_t i;